Cartridge ammunition

ABSTRACT

A cartridge ammunition includes a cartridge case having a front and a rear; a projectile inserted into the cartridge case at its front and extending into the cartridge case; an igniter provided in the rear of the cartridge case; and a propellant charge accommodated in the cartridge case. The propellant charge is formed of a compacted bulk propellant powder having a density of between 0.9 and 1.2 g/cm 3 .

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application is a division of application Ser. No. 09/157,951filed Sep. 22, 1998.

[0002] This application claims the priority of German Application No.197 41 841.4 filed Sep. 23, 1997, which is incorporated herein byreference.

BACKGROUND OF THE INVENTION

[0003] This invention relates to cartridge ammunition.

[0004] German Offenlegungsschrift (application published withoutexamination) 41 39 269, to which corresponds U.S. Pat. No. 5,335,599,discloses a cartridge having a combustible cartridge case which, forincreasing performance, has three partial charges: a high charge-densityfirst partial charge which is a compressed propellant powder and whichis disposed between the rear of the projectile and the cartridge base, asecond partial charge which is a bulk propellant powder and which issituated at that side of the cartridge case which is oriented towardsthe projectile tip, and a third partial charge situated between thefirst and second partial charges. The third partial charge is arod-shaped propellant which may also contain bulk propellant powdershaken into the space accommodating the rod propellant.

[0005] It is one of the disadvantages of the above-outlined knowncartridge that the second partial charge, because of its low chargedensity, contributes only slightly—if at all—to the desired performanceincrease of the cartridge. Further, the compression of the first partialcharge in the cartridge case leads to problems of reproducibility whichis particularly disadvantageous when firing cartridges at lowtemperatures. Also, introducing the propellant into the known cartridgeis a relatively time-consuming process.

SUMMARY OF THE INVENTION

[0006] It is an object of the invention to provide an improved cartridgeof the above-outlined type in which the second partial charge too,significantly contributes to the performance increase of the cartridge.

[0007] This object and others to become apparent as the specificationprogresses, are accomplished by the invention, according to which,briefly stated, the cartridge ammunition includes a cartridge casehaving a front and a rear; a projectile inserted into the cartridge caseat its front and extending into the cartridge case; an igniter providedin the rear of the cartridge case; and a propellant charge accommodatedin the cartridge case. The propellant charge is formed of a compactedbulk propellant powder having a density of between 0.9 and 1.2 g/cm³.

[0008] Essentially, the invention is based on the principle to use abulk propellant powder which is densely packed (compacted) by means of arotary vibrator. The rotary vibrator is arranged in such a manner thatits axis of rotation coincides with the longitudinal axis of thecartridge case. As a result of such a positional relationship, thevibrating process results in a parallelization of the longitudinal axesof the individual propellant powder grains with the longitudinal axis ofthe cartridge case, whereby a relatively high charge-density (packingdensity) of the propellant charge and thus a substantial performanceincrease of the cartridge are achieved.

[0009] Tests have shown that the frequency with which the rotaryvibrator is oscillated is preferably between 0.2 and 10 Hz and theamplitude of the pivotal motion is between 10 and 270° in order toachieve the predetermined compactness of the bulk powder propellantcharge in a relatively short time.

[0010] In accordance with an advantageous embodiment of the invention, afirst partial charge is provided not by compression in the cartridgecase, but as a stacked charge having a compactness which corresponds tothat of a compressed partial charge. Since stacked charges may be veryaccurately made, the cartridges accordingly have a reproducible innerballistic behavior even when fired at low temperatures. Further, byusing such charges as separately deliverable components, an introductionof such charges into the cartridge may be performed in a short period oftime.

[0011] According to another advantageous embodiment of the invention,the first partial charge too, is introduced into the cartridge case as abulk propellant powder compacted by the rotary vibrator until thedesired packing density is reached.

BRIEF DESCRIPTION OF THE DRAWING

[0012]FIG. 1 is an axial sectional view of a two-part cartridge madeaccording to the invention.

[0013]FIG. 2 is an enlarged sectional view taken along line II-II ofFIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014]FIG. 1 shows a cartridge 1 having a frontal cartridge case part 2and a rearward cartridge case part 3, separated from one another by acombustible disk 4 made, for example, of cardboard or textile fabric.

[0015] The rearward cartridge case part 3 is formed of a combustiblecomponent 5 secured to a metal case bottom 6, centrally supporting abottom igniter part 7 by a threaded connection. The cartridge case part3 accommodates a first partial charge 8 which is a stacked charge havinga packing density corresponding to the compressed material(≧1.2 g/cm³)used in comparable cartridges (such as disclosed in the earlier-notedGerman Offenlegungsschrift 41 38 269). The first partial charge 8defines an axial bore for receiving a metal ignition tube 9 which passesthrough the first partial charge 8 and which is supported on the bottomigniter part 7 to prevent it from lateral displacements.

[0016] The frontal cartridge case part 2 accommodates a fin-stabilized,subcaliber kinetic energy projectile 12 having a sabot 11 and extendingto the bottom 10 of the frontal cartridge case part 2. The latter isformed of a combustible component 13 which has a cylindrical portion 14and a frontal circumferential shoulder 15 whose forward end is inwardlycrimped for providing an engagement face for the sabot 11. The frontalcartridge case part 2 accommodates, in the space surrounded by theshoulder 15, a second partial charge 16 which is a bulk propellantpowder, compacted according to the invention by means of a rotaryvibrator (not illustrated) to a packing density of between approximately0.9 and 1.2 g/cm³.

[0017] In the frontal cartridge case part 2, between the second partialcharge 16 and the bottom plate 10, propellant rods are provided whichconstitute a third partial charge 17. The rods are packed closely to oneanother and extend over the length of the cylindrical portion 14. Forfilling dead spaces between the rods or between the rods on the one handand the rearward part 18 of the projectile 12 on the other hand, andthus for increasing the packing density of the third partial charge,additionally bulk propellant may be shaken into those locations.Further, between the second and the third partial charges 16 and 17 acombustible apertured disk 19 is provided.

[0018] In FIG. 2 the individual powder grains are designated at 20;arrow 21 indicates the direction of the oscillating motion of thecartridge during compacting of the propellant. Such an oscillatingmotion is performed about the longitudinal axis 22 of the cartridge withan amplitude of about approximately 150° at a frequency of preferablybetween 0.2 and 10 Hz.

[0019] In the description which follows a preferred embodiment of theinvention will be set forth.

[0020] The kinetic energy projectile 12 is inserted into the frontalcartridge case part 2 to assume a position as shown in FIG. 1. At thisstage, the frontal cartridge case part 2 has no propellant charges norare the bottom plates 4 and 19 present. Also, the frontal cartridge casepart 2 and the rearward cartridge case part 3 are not yet joined to oneanother.

[0021] Thereafter, the assembly formed by the frontal cartridge casepart 2 and the kinetic energy projectile 12 is placed in anon-illustrated rotary vibrator so that the kinetic energy projectile 12is pointing downward and the assembly axis 22 coincides with the rotaryaxis of the vibrator.

[0022] Then the rotary vibrator is set in motion such that the assembly2, 12 is oscillated with an amplitude of between 10 and 270° and with afrequency of between 0.2 and 10 Hz. Simultaneously, bulk propellantpowder is poured into the frontal cartridge part 2 from the top (thatis, through the presently open bottom of the cylindrical part 14),whereby the bulk powder will build up in the space which is surroundedby the shoulder portion 15 and, by virtue of the forces imparted on thepowder grains by the oscillation, the longitudinal axes of the grainswill be aligned parallel to the assembly axis 22. Thus, the rotaryvibrator causes a compacting of the bulk powder in the forward portionof the frontal cartridge case part 2, particularly in the space which issurrounded by the shoulder 15. Vibrating the assembly 2, 12 and pouringthe bulk powder are discontinued when the predetermined amount of bulkpowder has been placed into the frontal cartridge case portion 2 to thusconstitute the second propellant charge 16.

[0023] As a next step, the perforated disk 19 is inserted in the frontalcartridge case part 2 and then the powder rods forming the thirdpropellant charge 17 are positioned in the cylindrical portion 14 of thefrontal cartridge case part 2. To fill out dead spaces, bulk powder maybe shaken into the cylindrical part 14 to fill the spaces between therods and between the rods and the cylindrical portion 14. It is alsofeasible to again oscillate the assembly 2, 12 in the above-describedmanner for compacting the bulk powder propellant occupying thecylindrical part 14.

[0024] Thereafter the combustible disk 4 is inserted to form the bottomof the frontal cartridge case part 2.

[0025] As a last step, the rearward cartridge case part 3 is secured tothe frontal cartridge part 2, for example, by gluing. The rearwardcartridge case part 3 was previously filled with the stacked chargeforming the first partial charge 8.

[0026] According to an alternative, the pouring and vibrating stepcontinues until the bulk powder substantially entirely fills thecylindrical portion 14 of the frontal cartridge case part 2 as well. Insuch a case then the rod-shaped propellant powder and the apertured disk19 are omitted. Or, after the bulk powder has been compacted in thespace surrounded by the shoulder 15, the apertured disk 19 is insertedand then the pouring and the vibrating step continues to fill thecylindrical space 14 instead of providing the powder rods.

[0027] As a further alternative which may be combined with either methodconcerning the filling of the frontal cartridge case part 2, instead ofa stacked propellant charge, the first propellant charge 8 contained inthe rearward cartridge case part 5 may also be a bulk powder, compactedby a rotary vibrator as described in connection with the frontalcartridge case part 2. Both alternatives contribute to an economicmanufacture of the cartridge ammunition.

[0028] It is to be understood that the invention is not limited to thedescribed example. Thus, the cartridge need not be a two-part structure;the invention may find equally advantageous application in one-partcartridges as well.

[0029] The packing densities of the partial charges should be preferablybetween 0.9 and 1.2 g/cm³.

[0030] It will further be understood that the above description of thepresent invention is susceptible to various modifications, changes andadaptations, and the same are intended to be comprehended within themeaning and range of equivalents of the appended claims.

What is claimed is:
 1. Cartridge ammunition comprising (a) a cartridgecase having a front and a rear; (b) a projectile inserted into saidcartridge case at said front thereof; said projectile extending intosaid cartridge case; (c) an igniter provided in said cartridge case atsaid rear thereof; and (d) a propellant charge accommodated in saidcartridge case; said propellant charge being formed of a compacted bulkpropellant powder having a density of between 0.9 and 1.2 g/cm³.
 2. Thecartridge ammunition as defined in claim 1 , wherein said propellantcharge is a second propellant charge extending from the front of saidcartridge case rearwardly; further comprising a first propellant chargeextending from the rear of said cartridge case forwardly; and furtherwherein said first propellant charge is formed of stacked propellantpowder.
 3. The cartridge ammunition as defined in claim 2 , wherein saidstacked propellant powder has a packing density of ≧1.2 g/cm³.
 4. Thecartridge ammunition as defined in claim 1 , wherein said propellantcharge is a second propellant charge extending from the front of saidcartridge case rearwardly; further comprising a first propellant chargeextending from the rear of said cartridge case forwardly; furtherwherein said first propellant charge is formed of a compacted bulkpropellant powder having a density of between 0.9 and 1.2 g/cm².
 5. Thecartridge ammunition as defined in claim 1 , wherein said propellantcharge is a second propellant charge extending from the front of saidcartridge case rearwardly; further comprising a first propellant chargeextending from the rear of said cartridge case forwardly and a thirdpropellant charge disposed in said cartridge case between said first andsecond propellant charges.
 6. The cartridge ammunition as defined inclaim 5 , wherein said third propellant charge is formed of propellantpowder rods.
 7. The cartridge ammunition as defined in claim 5 , whereinsaid third propellant charge is formed at least in part of a compactedbulk propellant powder having a density of between 0.9 and 1.2 g/cm³.